Electric power control system, electric power control method, and control device, data storage medium, and server device for the same

ABSTRACT

A power control system comprises a power accumulating system including a storage cell charged with electric power supplied from a power generating system and supplying a vehicle with electric power, and a control device controlling a cumulative power amount that is an amount of electric power accumulated in the storage cell. The power control system accepts drive schedule data representing whether or not the vehicle is to be used during a predetermined period. The power control system charges the storage cell till the cumulative power stored in the storage cell reaches a first threshold when the drive schedule data represents the vehicle is to be used during the period, or otherwise, it charges the storage cell till the cumulative power stored in the storage cell reaches a second threshold smaller than the first threshold when the drive schedule data represents the vehicle is not to be used during the period.

CROSS-REFERENCE TO THE RELATED APPLICATIONS

The present invention is Continuation of U.S. patent application Ser.No. 13/085,663, which claims priority from Japanese Patent ApplicationNo. 2010-101976 filed on Apr. 27, 2010, the contents of all of which areincorporated herein by reference, in their entirety.

FIELD OF THE INVENTION

The present invention relates to a power control system supplyingelectric power to power accumulating systems provided with power storagecells.

BACKGROUND ART

A power control system is well known in the art which comprises a powergenerating system capable of generating electric power, and poweraccumulating systems provided with storage cells that are adapted to becharged with electric power from the power generating system and tosupply a vehicle with electric power for propulsion thereof (see PatentDocument 1).

BACKGROUND ART DOCUMENTS Patent Documents

-   Patent Document 1: Japanese Patent Preliminary Publication of    Unexamined

SUMMARY OF THE INVENTION Problems to be Solved by the Invention

It is very usual that a driver uses (rides) a vehicle during daytimeonly. Hence, a storage cell carried within the vehicle is to be chargedmostly at night. Thus, there arises a problem that especially when apower control system consists of a relatively large number of poweraccumulating systems, an amount of electric power supplied from thepower generating system to the power accumulating systems over night isprone to be excessive. In order to address this problem, the powercontrol system adapted to accumulate and store a relatively reducedamount of electric power in the storage cells is contemplated, but sucha power control system results in the storage cells being charged onlyinsufficiently in cumulative amount of electric power if the vehicleshave been in use and consuming energy.

Accordingly, it is an object of the present invention to provide theimproved power control system bringing forth a solution to theaforementioned problems in the background art that the storage cell ischarged only insufficiently in cumulative power amount while the vehiclehas been in use and consuming energy, and that an amount of electricpower supplied from the power generating system to the poweraccumulating systems is excessive.

Means to Solve the Problems

To fulfill the object of the present invention, a power control systemin one aspect of the present invention comprises:

a power generating system for generating electric power,

a power accumulating system provided with a storage cell that is chargedwith electric power supplied from the power generating system and supplya vehicle with electric power for propulsion thereof, and a powercontrol device for controlling a cumulative power amount that is anamount of electric power accumulated in the storage cell,

a drive schedule acceptance unit for accepting drive schedule data thatrepresents whether or not the vehicle is to be used during apredetermined period in the future, and

a cumulative power amount control unit for charging the storage cellwith electric power till the cumulative power amount reaches a firstthreshold if the accepted drive schedule data represents the vehicle isto be used during the period, or otherwise, charging the storage cellwith electric power till the cumulative power amount reaches a secondthreshold lower than the first threshold if the accepted drive scheduledata represents the vehicle is not to be used during the period.

In another aspect of the present invention, a power control method isapplicable to a power control system that includes:

a power generating system for generating electric power, and

a power accumulating system provided with a storage cell that is chargedwith electric power supplied from the power generating system and supplya vehicle with electric power for propulsion thereof, and a controldevice for controlling a cumulative power amount that is an amount ofelectric power accumulated in the storage cell,

the power control method comprising:

accepting drive schedule data that represents whether or not the vehicleis to be used during a predetermined period in the future, and

charging the storage cell with electric power till the cumulative poweramount reaches a first threshold if the accepted drive schedule datarepresents the vehicle is to be used during the period, or otherwise,charging the storage cell with electric power till the cumulative poweramount reaches a second threshold lower than the first threshold if thedrive schedule data represents the vehicle is not to be used during theperiod.

In still another aspect of the present invention, a control device isadapted to control a cumulative power amount that is an amount ofelectric power accumulated in a storage cell that is charged withelectric power supplied from a power generating system and supplies avehicle with electric power for propulsion thereof,

the control device comprising:

a drive schedule acceptance unit for accepting drive schedule data thatrepresents whether or not the vehicle is to be used during apredetermined period in the future, and

a cumulative power amount control unit for charging the storage cellwith electric power till the cumulative power amount reaches a firstthreshold if the accepted drive schedule data represents the vehicle isto be used during the period, or otherwise, charging the storage cellwith electric power till the cumulative power amount reaches a secondthreshold lower than the first threshold if the drive schedule datarepresents the vehicle is not to be used during the period.

In further another aspect of the present invention, a computer-readabledata storage medium stores a computer program that comprises at least aset of instructions executable by an information processing deviceadapted to control a cumulative power amount that is an amount ofelectric power accumulated in a storage cell that is charged withelectric power supplied from an electric power generating system andsupplies a vehicle with electric power for propulsion thereof,

the instructions including:

accepting drive schedule data that represents whether or not the vehicleis to be used during a predetermined period in the future, and

charging the storage cell with electric power till the cumulative poweramount reaches a first threshold if the accepted drive schedule datarepresents the vehicle is to be used during the period, or otherwise,charging the storage cell with electric power till the cumulative poweramount reaches a second threshold lower than the first threshold if thedrive schedule data represents the vehicle is not to be used during theperiod.

In further another aspect of the present invention, a server devicecomprises:

a drive schedule reception unit for receiving drive schedule data thatrepresents whether or not a vehicle is to be used during a predeterminedperiod in the future, the drive schedule data being received from acontrol device adapted to control a cumulative power amount that is anamount of electric power accumulated in a storage cell, the storage cellbeing charged with electric power supplied from an electric powergenerating system which generates electric power and supplying thevehicle with electric power for propulsion thereof,

a threshold cumulative power amount control unit for determining a lowerlimit of the cumulative power amount based on the received driveschedule data, the lower limit being a second threshold smaller than afirst threshold that is an upper limit of the cumulative power amount,and

a threshold cumulative power amount transmission unit for transmittingthe determined second threshold to the control device.

In yet another aspect of the present invention, a computer-readable datastorage medium stores a computer program comprising at least a set ofinstructions executable by an information processing device adapted tocontrol a cumulative power amount that is an amount of electric poweraccumulated in a storage cell that is charged with electric powersupplied from an electric power generating system and supplies a vehiclewith electric power for propulsion thereof,

the instructions including:

receiving drive schedule data that represents whether or not the vehicleis to be used during a predetermined period in the future, the driveschedule data being received from a control device adapted to control acumulative power amount that is an amount of electric power accumulatedin a storage cell, the storage cell being charged with electric powersupplied from an electric power generating system and supplying thevehicle with electric power for propulsion thereof,

determining a lower limit of the cumulative power amount based on thereceived drive schedule data, the lower limit being a second thresholdsmaller than a first threshold that is an upper limit of the cumulativepower amount, and

transmitting the value of the determined second threshold to the controldevice.

A power control system in further another aspect of the presentinvention comprises:

a power generating system for generating electric power,

a power accumulating system provided with a storage cell that is chargedwith electric power supplied from the power generating system and supplya vehicle with electric power for propulsion thereof, and a powercontrol device for controlling a cumulative power amount that is anamount of electric power accumulated in the storage cell,

a drive schedule acceptance means for accepting drive schedule data thatrepresents whether or not the vehicle is to be used during apredetermined period in the future, and

a cumulative power amount control means for charging the storage cellwith electric power till the cumulative power amount reaches a firstthreshold if the accepted drive schedule data represents the vehicle isto be used during the period, or otherwise, charging the storage cellwith electric power till the cumulative power amount reaches a secondthreshold lower than the first threshold if the accepted drive scheduledata represents the vehicle is not to be used during the period.

In still another aspect of the present invention, a control device isadapted to control a cumulative power amount that is an amount ofelectric power accumulated in a storage cell that is charged withelectric power supplied from a power generating system and supplies avehicle with electric power for propulsion thereof,

the control device comprising:

a drive schedule acceptance means for accepting drive schedule data thatrepresents whether or not the vehicle is to be used during apredetermined period in the future, and

a cumulative power amount control means for charging the storage cellwith electric power till the cumulative power amount reaches a firstthreshold if the accepted drive schedule data represents the vehicle isto be used during the period, or otherwise, charging the storage cellwith electric power till the cumulative power amount reaches a secondthreshold lower than the first threshold if the drive schedule datarepresents the vehicle is not to be used during the period.

In further another aspect of the present invention, a server devicecomprises:

a drive schedule reception means for receiving drive schedule data thatrepresents whether or not a vehicle is to be used during a predeterminedperiod in the future, the drive schedule data being received from acontrol device adapted to control a cumulative power amount that is anamount of electric power accumulated in a storage cell, the storage cellbeing charged with electric power supplied from an electric powergenerating system which generates electric power and supplying thevehicle with electric power for propulsion thereof,

a threshold cumulative power amount control means for determining alower limit of the cumulative power amount based on the received driveschedule data, the lower limit being a second threshold smaller than afirst threshold that is an upper limit of the cumulative power amount,and

a threshold cumulative power amount transmission means for transmittingthe determined second threshold to the control device.

Effect of the Invention

The present invention, configured in any of the aforementioned manners,is capable of avoiding a shortage of the cumulative power stored in thestorage cell while the vehicle has been in use on schedule, and iscapable of preventing the electric power generating system fromsupplying the power accumulating system with an excessive amount ofelectric power.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a schematic diagram illustrating a part related to powertransmission in a first exemplary embodiment of a power control systemaccording to the present invention;

FIG. 2 is a schematic diagram illustrating a part related to datacommunication in the first exemplary embodiment of the power controlsystem according to the present invention;

FIG. 3 is a schematic block diagram illustrating functions of the firstexemplary embodiment of the power control system according to thepresent invention;

FIG. 4 is a flow chart illustrating a cumulative power amount controlprogram executed by the CPU of a control device in the first exemplaryembodiment of the present invention;

FIG. 5 is a flow chart illustrating a threshold cumulative power amountdetermination program executable by the CPU of a server device in thefirst exemplary embodiment of the present invention;

FIG. 6 is a schematic block diagram illustrating functions of a secondexemplary embodiment of the power control system according to thepresent invention;

FIG. 7 is a schematic diagram illustrating a power accumulating systemin a third exemplary embodiment of the present invention;

FIG. 8 is a schematic block diagram illustrating functions of the thirdexemplary embodiment of the power control system according to thepresent invention; and

FIG. 9 is a schematic block diagram illustrating functions of a fourthexemplary embodiment of the power control system according to thepresent invention.

EXEMPLARY EMBODIMENT

Exemplary embodiments of a power control system, a power control method,and a control device, a data storage medium, and a server device for thesame according to the present invention will now be described in detail,with reference to FIGS. 1 to 9.

Exemplary Embodiment 1 System Architecture

As shown in FIG. 1, a first exemplary embodiment of a power controlsystem 1 is comprised of a power generating system 2, a plurality ofpower accumulating systems 3 a, 3 b, and so forth, a plurality of loads6 a, 6 b, and so forth. The power generating system 2, the poweraccumulating systems 3, and the loads 6 are interconnected via wiring PLconstituting power distribution network so that the power generatingsystem 2 distributes electric power to each of the power accumulatingsystems 3 and each of the loads 6.

The power generating system 2 generates electric power. In thisembodiment, the power generating system 2 produces electric powerthrough any of thermal power generation, waterpower generation, atomicpower generation, and wind power generation. Electricity produced by thepower generating system 2 (i.e., the electric power supplied by thepower generating system 2) is referred to as system power supply(external energizer).

The power accumulating system 3 a includes a storage cell 31 a and acontrol device 32 a.

The storage cell 31 a is able to be charged with electric power suppliedfrom the power generating system 2. The storage cell 31 a supplies avehicle (not shown) with electric power for propulsion of the vehicle.In this embodiment, the storage cell 31 a is carried within the vehicle.The storage cell 31 a is also referred to as secondary battery orrechargeable battery (energizer battery).

The control device 32 a controls a cumulative power amount that is anamount of electric power accumulated in the storage cell 31 a. In thisembodiment, the power accumulating system 3 a is placed in a residence.

Besides the power accumulating system 3 a, the remaining poweraccumulating systems 3 b and the like are similarly configured.Specifically, the power accumulating system 3 b includes a storage cell31 b and a control device 32 b.

The loads 6 consume electric power supplied by the power generatingsystem 2. For instance, each of the loads 6 may be a device actuated byelectric power.

In addition, the power control system 1 includes a server device 21, ascan be seen in FIG. 2. The server device 21 and the control devices 32are interconnected via communication lines NW so as to permit datacommunication among them.

The server device 21 is an information processing device. The serverdevice 21 includes a central processing unit (not shown) and a datastorage device (e.g., a memory or a hard disk drive). As a result ofCPU's executing a program stored in the data storage device, the serverdevice 21 carries out functions as mentioned below.

Similar to the server device 21, the control devices 32 have theirrespective CPUs (not shown) and data storage devices. Also similar tothe server device 21, each of the control devices 32 performs functionsas mentioned below, as a result of CPUs' executing a program stored inits data storage device.

(Functions)

FIG. 3 is a block diagram illustrating part of a variety of functionunits of the power control system 1, especially, the function units ofthe control device 32 a and the server device 21, respectively. Theremaining control devices 32 b and the like carry out the same functionsas the control device 32 a does.

The control device 32 a includes the function units such as a driveschedule acceptance unit (drive schedule acceptance means) 41, a driveschedule transmission unit (drive schedule transmission means) 42, athreshold reception (threshold cumulative power amount reception) unit(threshold reception means) 43, and a cumulative power amount controlunit (cumulative power amount control means) 44.

The server device 21 has the function units such as a drive schedulereception unit (drive schedule reception means) 51, a thresholdcumulative power amount determination unit (threshold cumulative poweramount determination means) 52, and a threshold cumulative power amounttransmission unit (threshold cumulative power amount transmission means)53.

The drive schedule acceptance unit 41 in the control device 32 a permitsa user to input drive schedule data to accept it. The drive scheduledata is information on whether or not a vehicle is to be used during apredetermined period in the future (e.g., from 9 a.m. to 9 p.m. nextday, from 5 a.m. to 11 p.m the day after tomorrow, or the like).

In this embodiment, the control device 32 a has a button type of switch.When the switch is pressed by the user in confirmation of thepredetermined period input by himself or herself, the drive scheduleacceptance unit 41 produces the drive schedule data representing thatthe vehicle is to be used during the predetermined period, and thus, itcompletes registration of the drive schedule data. Reversely, when theswitch is not pressed by the user in confirmation of the predeterminedperiod input by himself or herself, the drive schedule acceptance unit41 produces the drive schedule data representing the vehicle is not tobe used during the predetermined period, and thus, it completesregistration of the drive schedule data.

Alternatively the control device 32 a may receive the drive scheduledata from an information processing device (e.g., a personal computer)intercommunicating therewith to accept the drive schedule data.

The drive schedule data transmission unit 42 in the control device 32 atransmits the drive schedule data accepted by the drive scheduleacceptance unit 41 to the server device 21.

The drive schedule reception unit 51 in the server device 21 receivesthe drive schedule data from the control device 32 a.

The threshold cumulative power amount determination unit 52 determines alower (second) threshold of a cumulative amount of supplied electricpower, from the drive schedule data received by the drive schedulereception unit 51. The threshold cumulative power amount determinationunit 52 determines the second threshold smaller than an upper (first)threshold of the cumulative amount of supplied electric power. Herein,the first threshold refers to an amount of electric power accumulated inthe storage cell 31 a in the case that the storage cell is fullycharged.

More specifically, the threshold cumulative power amount determinationunit 52 determines the second threshold at a value that becomes smalleras the number of the control devices 32 transmitting the drive scheduledata representing the vehicle is to be used during the period becomesgreater.

The greater the number of the vehicles to be used during the period is,the higher the amount of electric power to be supplied from the powergenerating system 2 to the power accumulating systems 3 becomes. Thus,setting the second threshold at a value that becomes smaller as thenumber of the vehicles to be used during the predetermined period isincreased, an amount of the electric power to be supplied from the powergenerating system 2 to the power accumulating systems 3 (e.g., themaximum value or the peak value of the power to be supplied) can beprevented from getting excessive.

The threshold cumulative power amount transmission unit 53 in the serverdevice 21 transmits the value of the second threshold determined by thethreshold cumulative power amount determination unit 52 to the controldevice 32 a.

The threshold reception unit 43 in the control device 32 a receives thevalue of the second threshold from the server device 21.

When the drive schedule data accepted by the drive schedule acceptanceunit 41 represents the vehicle is to be used during the period, thecumulative power amount control unit 44 in the control device 32 acharges the storage cell 31 a with electric power till the power amountaccumulated in the storage cell 31 a reaches the first threshold.

On the other hand, when the drive schedule data accepted in the driveschedule acceptance unit 41 represents the vehicle is not to be usedduring the period, the cumulative power amount control unit 44 chargesthe storage cell 31 a with electric power till the power amountaccumulated in the storage cell 31 a reaches the second thresholdreceived by the threshold reception unit 43.

(Operation)

Operation of the power control system 1 described so far will now bedescribed.

Every time the predetermined period input by the user expires, thecontrol device 32 a executes a cumulative power amount control programillustrated in the flow chart of FIG. 4.

Specifically, once it starts execution of the cumulative power amountcontrol program, the control device 32 a stands by till the driveschedule data is accepted.

Succeeding stages of the operation will be detailed below on theassumption that the drive schedule data representing the vehicle is tobe used during the period has been accepted in the control device 32 a.

In this case, the control device 32 a passes an affirmative judgment‘YES’ at Step S101 and goes to Step S102 where it is instructed totransmit the accepted drive schedule data to the server device 21. Then,the control device 32 a takes the next step to S103 where it isinstructed to stand by till the second threshold is received from theserver device 21.

On the other hand, each time a predetermined standby duration elapsesafter the expiration time of the predetermined period input by the user,the server device 21 executes a threshold cumulative power amountdetermination program illustrated in the flow chart of FIG. 5.

Specifically, once it starts execution of the threshold cumulative poweramount determination program, the server device 21 stands by till thedrive schedule data is received from every one of the control devices 32belonging to the power control system 1 (Step S201).

Upon receiving the drive schedule data from all the control devices 32in the power control system 1, the server device 21 passes anaffirmative judgment ‘YES’ and goes to Step S202 where it is instructedto determine the second threshold of the cumulative amount of suppliedelectric power.

In this embodiment, the server device 21 determines the second thresholdat a value that becomes smaller as the number of the control devices 32transmitting the drive schedule data representing the vehicle is to beused during the period becomes greater.

Then, the server device 21 transmits the second threshold thusdetermined to all the control devices 32 belonging to the power controlsystem 1. In this way, the server 21 terminates the processing by thethreshold cumulative power amount determination program.

This permits the control device 32 a to receive from the server device21 the value of the second threshold of the cumulative amount ofsupplied electric power. Thus, the control device 32 a passes anaffirmative judgment ‘YES’ at step S103 to go to the next step S104.

After that, regarding the drive schedule data accepted at step S101, thecontrol device 32 a determines whether or not it contains informationrepresenting the vehicle is to be used during the period (i.e., if thevehicle is scheduled to be used) (Step S104).

According to the above-mentioned assumption, the accepted drive scheduledata contains information representing the vehicle is to be used duringthe period. Thus, the control device 32 a passes an affirmative judgment‘YES’ and takes the next step to S105 where it is instructed to chargethe storage cell 31 a with electric power till the cumulative poweramount in the storage cell 31 a reaches the first threshold. Eventually,the control device 32 a terminates the processing by the cumulativepower amount control program.

Next, detailed below will be a case in which the drive schedule datarepresenting the vehicle is not to be used during the period is acceptedby the control device 32 a.

In this case, the control device 32 a passes a negative judgment ‘NO’ togo to Step S106 where it is instructed to charge the storage cell 31 awith electric power till the cumulative power amount stored in thestorage cell 31 a reaches the second threshold received at Step S103.Thus, the control device 32 a terminates the processing by thecumulative power amount control program.

Alternatively, if the drive schedule data representing the vehicle is tobe used during the period is accepted, the control device 32 a mayproceed to Step S104 instead of waiting for reception of the value ofthe second threshold from the server device 21 (i.e., it may omitexecution of the instruction at Step S103).

As has been described, the power control system 1 in the first exemplaryembodiment of the present invention can reduce an amount of electricpower to be supplied from the power generating system 2 to the poweraccumulating systems 3 if the vehicles are not to be used during theperiod, in comparison with the case where the power control system isadapted to charge the storage cell with electric power till thecumulative power amount stored in the storage cell reaches the firstthreshold.

Moreover, the power control system 1 is adapted to charge the storagecells 31 with electric power till the cumulative power amount stored inthe storage cells 31 reaches the first threshold if the vehicle is to beused during the period. Thus, it can be avoided that the storage cells31 come to be short of power while the vehicle has been in use.

In this way, the power control system 1 is capable of avoiding ashortage of the electric power stored in the storage cells 31 while thevehicle has been in use on schedule, and is capable of preventing theelectric power generating system 2 from supplying the power accumulatingsystems 3 with an excessive amount of electric power.

Furthermore, in the power control system 1 of the first exemplaryembodiment, the first threshold is an amount of electric poweraccumulated in the storage cells 31 to the full extent of theircapacities.

In this way, while the vehicle has been in use, a shortage of theelectric power stored in the storage cells 31 can be more effectivelyavoided.

The power control system 1 in the first exemplary embodiment has thecontrol devices 32 that accept the drive schedule data, andalternatively, the server device 21 may accept the drive schedule data.In the latter case, the server device 21 is preferably adapted totransfer the drive schedule data accepted thereby to the control devices32.

Exemplary Embodiment 2

A second exemplary embodiment of the power control system according tothe present invention will now be described. The power control system inthe second exemplary embodiment makes a difference from the one in thefirst exemplary embodiment in that the electric power stored in thestorage cells belonging to the power accumulating systems can besupplied to some other loads connected to the power generating system.Thus, such a difference will be a center topic of the followingdiscussion.

(System Architecture)

The power control system 1 in the second exemplary embodiment has apower generating system 2, power accumulating systems 3 a, 3 b and soforth, and loads 6 a, 6 b and so forth are interconnected via wiring PLconstituting power distribution network so that they mutually transferelectric power to one another.

The power accumulating systems 3 a, 3 b, and so forth in the secondexemplary embodiment are adapted to transfer the electric power storedin the storage cells 31 a, 31 b, and so forth in the power accumulatingsystems 3 to the residuary loads 6 connected to the power generatingsystem 2 when the vehicle has not been in use (i.e., the storage cells31 carried within the vehicle has been connected to the wiring PL).

(Functions)

As shown in FIG. 6, the server device 21 in the second exemplaryembodiment functions the same as the one in the first exemplaryembodiment and also has an additional functional component of underpowerestimation unit (underpower estimation means) 54.

The underpower estimation unit 54 estimates a deficit power amount thatis an amount of electric power supplied from the power generating system2 to predictably be short of during a predetermined period in the futureinput by a user for which a vehicle is to be used. In this embodiment,the underpower estimation unit 54 estimates the deficit power amountfrom weather data during the predetermined period, calendar data (e.g.,data on what day of the week each day is, on whether or not each day isa holiday, and the like) during the period, power consumption datarepresenting an amount of electric power to predictably be consumedduring the period, and operation data represents running conditions ofthe power generating system 2.

In the power control system 1, electric power to be consumed isrecognized as being varied depending upon weather, calendar day andmonth (e.g., the first to fifth weekdays, holidays, etc.), and the like.An amount of electric power produced by the power generating system 2 islikely to be varied depending upon its running conditions. Thus,configured in the aforementioned manner, the power control system 1 iscapable of estimating the deficit power amount with the enhancedaccuracy.

The threshold cumulative power amount control unit 52 determines a lower(second) threshold of a cumulative amount of electric power from thedeficit power amount estimated by the underpower estimation unit 54 andthe drive schedule data received from the drive schedule reception unit51. Specifically, the threshold cumulative power amount control unit 52determines the second threshold at a value that becomes higher as thegreater figure is given as the estimated deficit power amount anddetermines it at a value that becomes smaller as the greater number ofcontrol devices 32 a, 32 b, and so forth transmit the drive scheduledata representing the vehicle is to be used during the period (as thegreater number of vehicles are to be used).

While the vehicle has been used, it is impossible to supply power fromthe storage cells 31 in the power accumulating systems 3 to theresiduary loads 6 connected to the power generating system 2. Thus,configured as mentioned above, the power control system 1 is capable ofmore assuredly avoiding a shortage of the electric power to be suppliedto the loads 6 connected to the power generating system 2.

In this embodiment, the threshold cumulative power amount control unit52 sets the second threshold of the cumulative power amount at acomputation resulted from dividing the estimated deficit power amount bythe difference of the number of the vehicles to be used in the futuresubtracted from the total number of the control devices 32 and furthermultiplying the resultant quotient by a predetermined factor.

As has been described, the power control system 1 in the secondexemplary embodiment of the present invention is capable of divertingthe power stored in the storage cells 31 in the power accumulatingsystems 3 to energize the loads 6 connected to the power generatingsystem 2 (which normally should have been energized by the powergenerating system 2) in the event of a shortage of the electric powersupplied from the power generating system 2. In addition, setting thesecond threshold sufficient to charge the storage cells 31 with thepredicted deficit power amount or even more of electric power, the powercontrol system is capable of avoiding a shortage of the electric powerto be supplied to the residuary loads 6 connected to the powergenerating system 2.

Exemplary Embodiment 3

A third exemplary embodiment of the power control system according tothe present invention will now be described. The power control system inthe third exemplary embodiment is distinctive from the second exemplaryembodiment in that power accumulating systems themselves produceelectric power that is able to be supplied to the residuary loadsconnected to the power generating system. Accordingly, such a differencewill be a center topic of the following discussion.

(System Architecture)

As shown in FIG. 7, the power accumulating system 3 a in the thirdexemplary embodiment of the present invention is configured almost thesame as its counterpart in the second exemplary embodiment except thatit additionally has a power supply unit (power supply means) 33 a. Thepower supply unit 33 a itself generates electric power and supplies itto the residuary loads 6 a, 6 b, and so forth connected to the powergenerating system 2. In this embodiment, the power supply unit 33 a isadapted to generate power through at least one of solar power generationand wind power generation.

Alternatively, the power supply unit 33 a may have a secondary batterycharged with the electric power thus generated (i.e., additional storagecell besides a storage cell 31 a). The power accumulating system 3 a maybe adapted to charge the storage cell 31 a the power generated by thepower supply unit 33 a.

Besides the power accumulating system 3 a, the remaining poweraccumulating systems 3 b and so forth also have their respective powersupply units 33 b and so forth similar to the power accumulating system3 a.

(Functions)

As shown in FIG. 8, the server device 21 in the third exemplaryembodiment includes a surplus power estimation unit (surplus powerestimation means) 55 in addition to all the function units in theservice device 21 in the second exemplary embodiment.

The surplus power estimation unit 55 estimates a surplus power amountthat is an amount of electric power available to supply from the powersupply units 33 to the residuary loads 6 connected to the powergenerating system 2 during a predetermined period in the future input bya user. In this embodiment, the surplus power estimation unit 55estimates the surplus power amount from weather data representingweather during the period.

The more the weather is unfavorable (the shorter the sunshine durationis), the less an amount of electric power generated through solar powergeneration becomes. Thus, the shorter the sunshine duration is, the lessthe surplus power amount becomes. In addition, the weaker the wind blows(i.e., the lower the wind speed is), the less an amount of electricpower generated through wind power generation becomes. Thus, the lowerthe wind speed is, the less the surplus power amount becomes.

Allowing for the above, in this embodiment, the surplus power estimationunit 55 estimates the surplus power amount as a value that becomessmaller as the sunshine duration reported by the weather data is shorterand as the lower wind speed is predicted by the weather data. In thisway, the surplus power amount can be estimated with the enhancedaccuracy.

The threshold cumulative power amount control unit 52 determines a lower(second) threshold of the cumulative power amount from the surplus poweramount estimated by the surplus power estimation unit 55, the deficientpower amount estimated by the underpower estimation unit 54, and thedrive schedule data received by the drive schedule reception unit 51.

Specifically, the threshold cumulative power amount determination unit52 determines the second threshold at a value that becomes smaller asthe greater figure is given as the estimated surplus power amount and asthe greater number of control devices 32 a, 32 b, and so forth transmitthe drive schedule data representing the vehicle is to be used duringthe period (as the greater number of vehicles are to be used).

In this embodiment, the threshold cumulative power amount determinationunit 52 determines the second threshold at a value obtained from anarithmetic operation where a first value is computed by subtracting thenumber of vehicles to be used in the near future from the total numberof the control devices 32 while a second value is computed bysubtracting the estimated surplus power amount from the predicteddeficit power amount, and the second value thus computed is divided bythe first value and then multiplied by a predetermined factor.

As has been described, the power control system 1 in the third exemplaryembodiment according to the present invention is capable of divertingthe power generated by the power accumulating systems 3 to energize theloads 6 connected to the power generating system 2 (which normallyshould have been energized by the power generating system 2) in theevent of a shortage of the electric power supplied from the powergenerating system 2. Thus, setting the second threshold based on thedeficit power amount and the surplus power amount, the power controlsystem 1 is capable of preventing a shortage of the electric power to besupplied to the residuary loads 6 connected to the power generatingsystem 2 and is simultaneously capable of avoiding the second thresholdfrom being set at an excessively great value.

Exemplary Embodiment 4

A fourth exemplary embodiment of the power control system according tothe present invention will now be described with reference to FIG. 9.

A power control system 100 in the fourth exemplary embodiment comprises:

a power generating system 110 generating electric power, and

a power accumulating system 120 that includes a storage cell 121 chargedwith electric power supplied from the power generating system andsupplying a vehicle with electric power for propulsion thereof, and acontrol device 122 controlling a cumulative power amount that is anamount of electric power accumulated in the storage cell 121.

Furthermore, the power control system 100 comprises:

a drive schedule acceptance unit (drive schedule acceptance means) 131for accepting drive schedule data that represents whether or not thevehicle is to be used during a predetermined period in the future, and

a cumulative power amount control unit (cumulative power amount controlmeans) 132 for charging the storage cell 121 with electric power tillthe cumulative power stored in the storage cell 121 reaches an upper(first) threshold when the drive schedule data represents the vehicle isto be used during the period, or otherwise, charging the storage cell121 with electric power till the cumulative power stored in the storagecell 121 reaches a lower (second) threshold smaller than the firstthreshold when the drive schedule data represents the vehicle is not tobe used during the period.

Configured in this manner, the power control system 1 is capable ofreducing an amount of the electric power to be supplied from the powergenerating system 110 to the power accumulating system 120 if thevehicle is not to be used during the predetermined period, in comparisonwith the power control system that is adapted to charge the storage cellwith electric power till it reaches the first threshold of thecumulative power amount.

The storage cell 121 is charged with electric power till it reaches thefirst threshold when the vehicle is to be used during the period. Thus,it can be avoided that the storage cell 121 comes to be short of powerwhile the vehicle has been in use.

In this way, the power control system 100 is capable of avoiding ashortage of the cumulative power stored in the storage cell 121 whilethe vehicle has been in use and is capable of preventing the powergenerating system 110 from supplying an excessive amount of electricpower to the power accumulating system 120.

Although the present invention has been described in the context of theexemplary embodiments thereof, the present invention should not belimited to the precise forms of the exemplary embodiments. Variousmodifications could be made to the architecture and particulars of thepresent invention by any person having ordinary skills in the artwithout departing from the true scope of the present invention.

In the aforementioned embodiments, the server device 21 and the controldevices 32 have their respective functions implemented by CPU'sexecuting a program (software program), and instead, the functions maybe implemented by means of hardware such as circuitry.

Although it is stored in the memory device in the aforementionedembodiments, the program may be stored in a computer readable storagemedium. Such a storage medium may be a portable medium, includingflexible disks, optical disks, magneto-optic disks, semiconductormemories, and the like.

Other variations of the aforementioned embodiments may be anycombination of the embodiments and the modifications thereof.

<Supplementary Notes>

The aforementioned embodiments may be partially or as a whole revised asin the following supplementary notes, but not limited to the descriptionas follows:

(Supplementary Note 1)

A power control system comprising:

a power generating system for generating electric power,

a power accumulating system provided with a storage cell that is chargedwith electric power supplied from the power generating system and supplya vehicle with electric power for propulsion thereof, and a powercontrol device for controlling a cumulative power amount that is anamount of electric power accumulated in the storage cell,

a drive schedule acceptance unit for accepting drive schedule data thatrepresents whether or not the vehicle is to be used during apredetermined period in the future, and

a cumulative power amount control unit for charging the storage cellwith electric power till the cumulative power amount reaches a firstthreshold if the accepted drive schedule data represents the vehicle isto be used during the period, or otherwise, charging the storage cellwith electric power till the cumulative power amount reaches a secondthreshold lower than the first threshold if the accepted drive scheduledata represents the vehicle is not to be used during the period.

Configured in this manner, the power control system can reduce an amountof the electric power to be supplied to the power generating system whenthe vehicle is not to be used during the period, in comparison with thecase where the power control system is adapted to charge the storagecell with electric power till the cumulative power amount stored thereinreaches the first threshold.

Moreover, when the vehicle is to be used during the period, the storagecell is charged with electric power till the cumulative power amountstored therein reaches the first threshold. Thus, it can be avoided thatthe storages cell comes to be short of power while the vehicle has beenin use.

In this manner, the power control system is capable of avoiding ashortage of the cumulative power stored in the storage cell while thevehicle has been in use, and is capable of preventing the powergenerating system from supplying the power accumulating system with anexcessive amount of electric power.

(Supplementary Note 2)

The power control system according to Supplementary Note 1, wherein thefirst threshold is an amount of electric power accumulated in thestorage cell in the case that the storage cell is fully charged.

Configured in this manner, the power control system can more assuredlyavoid a shortage of the cumulative power stored in the storage cell whenthe vehicle has been in use.

(Supplementary Note 3)

The power control system according to Supplementary Note 1 orSupplementary Note 2, wherein the power control system comprises aplurality of the power accumulating systems and a server deviceintercommunicating with each of the control devices of the plurality ofthe power accumulating systems,

each control device including the drive schedule acceptance unit, and adrive schedule transmission unit for transmitting the accepted driveschedule data to the server device,

the server device including a drive schedule reception unit forreceiving the drive schedule data from the control device, a thresholdcumulative power amount determination unit for determining the secondthreshold based on the received drive schedule data, and a thresholdcumulative power amount transmission unit for transmitting a value ofthe determined second threshold to the control device,

the control device including a threshold cumulative power amountreception unit for receiving the value of the second threshold from theserver device.

As the number of the vehicles to be used during the period is increased,an amount of the electric power to be supplied from the power generatingsystem to the power accumulating systems becomes greater. Thus, settingthe second threshold at a value that becomes smaller as the number ofthe vehicles to be used during the period is increased, the powergenerating system can be prevented from supplying the power accumulatingsystems with an excessive amount of electric power.

(Supplementary Note 4)

The power control system according to Supplementary Note 3, wherein thethreshold cumulative power amount determination unit is adapted to setthe second threshold at a value that becomes smaller as the number ofthe control devices transmitting the drive schedule data representingthe vehicle is to be used during the period becomes greater.

(Supplementary Note 5)

The power control system according to any of Supplementary Notes 1 to 4,wherein the power accumulating system is adapted to supply the electricpower stored in the storage cell to the residuary load connected to thepower generating system,

wherein the server device includes an underpower estimation unit forestimating a deficit power amount that is an amount of electric powersupplied from the power generating system to predictably be short ofduring the period, and

wherein the threshold cumulative power amount determination unit isadapted to determine the second threshold based on the estimated deficitcumulative power amount and the received drive schedule data.

Configured in this manner, the power control system is capable ofdiverting the power stored in the storage cell in the power accumulatingsystem to energize the residuary load connected to the power generatingsystem (which normally should have been energized by the powergenerating system) in the event of a shortage of the electric powersupplied from the power generating system. Moreover, setting the secondthreshold sufficient to charge the storage cell with the predicteddeficit power amount or even more of electric power, the power controlsystem is capable of avoiding a shortage of the electric power to besupplied to the residuary load connected to the power generating system.

(Supplementary Note 6)

The power control system according to Supplementary Note 5, wherein thethreshold cumulative power amount determination unit is adapted todetermine the second threshold at a value that becomes greater as thenumber of the control devices transmitting the drive schedule datarepresenting the vehicle is to be used during the period becomesgreater.

While the vehicle has been in use, it is impossible to supply power fromthe storage cell in the power accumulating system to the residuary loadconnected to the power generating system. Thus, configured as mentionedabove, the power control system is capable of more assuredly avoiding ashortage of the electric power to be supplied to the load connected tothe power generating system.

(Supplementary Note 7)

The power control system according to Supplementary Note 5 orSupplementary Note 6, wherein the power accumulating system includes apower supply unit adapted to generate electric power and supply thegenerated electric power to the residuary load connected to the powergenerating system,

wherein the server device includes a surplus power estimation unit forestimating a surplus power amount that is an amount of electric poweravailable to supply from the power supply unit to the residuary loadconnected to the power generating system during the period, and

wherein the threshold cumulative power amount determination unit isadapted to determine the second threshold based on the estimated deficitcumulative power amount, the estimated surplus power amount, and thereceived drive schedule data.

Configured in this manner, the power control system is capable ofdiverting the power generated by the power accumulating system toenergize the residuary loads connected to the power generating system(which normally should have been energized by the power generatingsystem) in the event of a shortage of the electric power supplied fromthe power generating system. Thus, determining the second thresholdbased on the deficit power amount and the surplus power amount, thepower control system is capable of preventing a shortage of the electricpower to be supplied to the residuary load connected to the powergenerating system and is simultaneously capable of avoiding the secondthreshold from being set at an excessively great value.

(Supplementary Note 8)

The power control system according to any of Supplementary Notes 5 to 7,wherein the power supply unit is adapted to generate electric powerthrough at least one of solar power generation and wind powergeneration, and

wherein the surplus power estimation unit is adapted to estimates thesurplus power amount based on weather data representing weather duringthe period.

Electric power generated through solar power generation or wind powergeneration is varied depending upon weather. Thus, configured as in theabove, the power control system is capable of estimating the surpluspower amount with the enhanced accuracy.

(Supplementary Note 9)

The power control system according to any of Supplementary Notes 5 to 8,wherein the underpower estimation unit is adapted to estimate thedeficit power amount based on at least one of weather data representingweather during the period, calendar data representing calendar duringthe period, power consumption data representing an amount of electricpower to predictably be consumed during the period by the residuary loadconnected to the power generating system, and operation datarepresenting running conditions of the power generating system.

Electric power to be consumed is varied depending upon weather, calendarday and month (e.g., the first to fifth weekdays, holidays, etc.), andthe like. An amount of electric power produced by the power generatingsystem is varied depending upon its running conditions. Thus, configuredin the aforementioned manner, the power control system is capable ofestimating the deficit power amount with the enhanced accuracy.

(Supplementary Note 10)

A power control method applicable to a power control system thatincludes:

a power generating system for generating electric power, and

a power accumulating system provided with a storage cell that is chargedwith electric power supplied from the power generating system and supplya vehicle with electric power for propulsion thereof, and a controldevice for controlling a cumulative power amount that is an amount ofelectric power accumulated in the storage cell,

the power control method comprising:

accepting drive schedule data that represents whether or not the vehicleis to be used during a predetermined period in the future, and

charging the storage cell with electric power till the cumulative poweramount reaches a first threshold if the accepted drive schedule datarepresents the vehicle is to be used during the period, or otherwise,charging the storage cell with electric power till the cumulative poweramount reaches a second threshold lower than the first threshold if thedrive schedule data represents the vehicle is not to be used during theperiod.

(Supplementary Note 11)

The power control method according to Supplementary Note 10, wherein thefirst threshold is the cumulative power amount stored in the storagecell in the case that the storage cell is fully charged.

(Supplementary Note 12)

The power control method according to Supplementary Note 10 orSupplementary Note 11, wherein the power control system comprises aplurality of the power accumulating systems and a server deviceintercommunicating with the control devices of the power accumulatingsystems, and the method includes:

accepting, by the control device, the drive schedule data,

transmitting, by the control device, the accepted drive schedule data tothe server device,

receiving, by the server device, the drive schedule data from thecontrol device,

determining, by the server device, the second threshold based on thereceived drive schedule data,

transmitting, by the server device, the value of the second thresholdthus determined, to the control device, and

receiving, by the control device, the value of the second threshold fromthe server device.

(Supplementary Note 13)

The power control method according to Supplementary Note 12, wherein thesecond threshold is determined at a value that becomes smaller as thenumber of the control devices transmitting the drive schedule datarepresenting the vehicle is to be used during the period becomesgreater.

(Supplementary Note 14)

A control device adapted to control a cumulative power amount that is anamount of electric power accumulated in a storage cell that is chargedwith electric power supplied from a power generating system and suppliesa vehicle with electric power for propulsion thereof,

the control device comprising:

a drive schedule acceptance unit for accepting drive schedule data thatrepresents whether or not the vehicle is to be used during apredetermined period in the future, and

a cumulative power amount control unit for charging the storage cellwith electric power till the cumulative power amount reaches a firstthreshold if the accepted drive schedule data represents the vehicle isto be used during the period, or otherwise, charging the storage cellwith electric power till the cumulative power amount reaches a secondthreshold lower than the first threshold if the drive schedule datarepresents the vehicle is not to be used during the period.

(Supplementary Note 15)

The control device according to Supplementary Note 14, wherein the firstthreshold is an amount of electric power accumulated in the storage cellin the case that the storage cell is fully charged.

(Supplementary Note 16)

The control device according to Supplementary Note 14 or SupplementaryNote 15, further comprising:

a drive schedule transmission unit for transmitting the accepted driveschedule to a server device, and

a threshold cumulative power amount reception unit for receiving fromthe server device the value of the second threshold determined based onthe drive schedule data.

(Supplementary Note 17)

A computer-readable data storage medium that stores a computer programcomprising at least a set of instructions executable by an informationprocessing device adapted to control a cumulative power amount that isan amount of electric power accumulated in a storage cell that ischarged with electric power supplied from an electric power generatingsystem and supplies a vehicle with electric power for propulsionthereof,

the instructions including:

accepting drive schedule data that represents whether or not the vehicleis to be used during a predetermined period in the future, and

charging the storage cell with electric power till the cumulative poweramount reaches a first threshold if the accepted drive schedule datarepresents the vehicle is to be used during the period, or otherwise,charging the storage cell with electric power till the cumulative poweramount reaches a second threshold lower than the first threshold if thedrive schedule data represents the vehicle is not to be used during theperiod.

(Supplementary Note 18)

The computer-readable data storage medium according to SupplementaryNote 17, wherein the first threshold is an amount of electric poweraccumulated in the storage cell in the case that the storage cell isfully charged.

(Supplementary Note 19)

The computer-readable data storage medium according to SupplementaryNote 17 or Supplementary Note 18, wherein the computer program furthercomprises the instructions of:

transmitting the accepted drive schedule data to a server device, and

receiving the value of the second threshold from the server device thesecond threshold determined based on the received drive schedule data.

(Supplementary Note 20)

A server device comprising:

a drive schedule reception unit for receiving drive schedule data thatrepresents whether or not a vehicle is to be used during a predeterminedperiod in the future, the drive schedule data being received from acontrol device adapted to control a cumulative power amount that is anamount of electric power accumulated in a storage cell, the storage cellbeing charged with electric power supplied from an electric powergenerating system which generates electric power and supplying thevehicle with electric power for propulsion thereof,

a threshold cumulative power amount control unit for determining a lowerlimit of the cumulative power amount based on the received driveschedule data, the lower limit being a second threshold smaller than afirst threshold that is an upper limit of the cumulative power amount,and

a threshold cumulative power amount transmission unit for transmittingthe determined second threshold to the control device.

(Supplementary Note 21)

The server device according to Supplementary Note 20, wherein thethreshold cumulative power amount transmission unit determines thesecond threshold at a value that becomes smaller as the number of thecontrol devices transmitting the drive schedule data representing thevehicle is to be used during the period becomes greater.

(Supplementary Note 22)

A computer-readable data storage medium that stores a computer programcomprising at least a set of instructions executable by an informationprocessing device adapted to control a cumulative power amount that isan amount of electric power accumulated in a storage cell that ischarged with electric power supplied from an electric power generatingsystem and supplies a vehicle with electric power for propulsionthereof,

the instructions including:

receiving drive schedule data that represents whether or not the vehicleis to be used during a predetermined period in the future, the driveschedule data being received from a control device adapted to control acumulative power amount that is an amount of electric power accumulatedin a storage cell, the storage cell being charged with electric powersupplied from an electric power generating system and supplying thevehicle with electric power for propulsion thereof,

determining a lower limit of the cumulative power amount based on thereceived drive schedule data, the lower limit being a second thresholdsmaller than a first threshold that is an upper limit of the cumulativepower amount, and

transmitting the value of the determined second threshold to the controldevice.

(Supplementary Note 23)

The computer-readable data storage medium according to SupplementaryNote 22, wherein the instruction of determining a lower limit of thecumulative power amount includes determining the second threshold at avalue that becomes smaller as the number of the control devicestransmitting the drive schedule data representing the vehicle is to beused during the period becomes greater.

(Supplementary Note 24)

A power control system comprising:

a power generating system for generating electric power,

a power accumulating system provided with a storage cell that is chargedwith electric power supplied from the power generating system and supplya vehicle with electric power for propulsion thereof, and a powercontrol device for controlling a cumulative power amount that is anamount of electric power accumulated in the storage cell,

a drive schedule acceptance means for accepting drive schedule data thatrepresents whether or not the vehicle is to be used during apredetermined period in the future, and

a cumulative power amount control means for charging the storage cellwith electric power till the cumulative power amount reaches a firstthreshold if the accepted drive schedule data represents the vehicle isto be used during the period, or otherwise, charging the storage cellwith electric power till the cumulative power amount reaches a secondthreshold lower than the first threshold if the accepted drive scheduledata represents the vehicle is not to be used during the period.

(Supplementary Note 25)

A control device adapted to control a cumulative power amount that is anamount of electric power accumulated in a storage cell that is chargedwith electric power supplied from a power generating system and suppliesa vehicle with electric power for propulsion thereof,

the control device comprising:

a drive schedule acceptance means for accepting drive schedule data thatrepresents whether or not the vehicle is to be used during apredetermined period in the future, and

a cumulative power amount control means for charging the storage cellwith electric power till the cumulative power amount reaches a firstthreshold if the accepted drive schedule data represents the vehicle isto be used during the period, or otherwise, charging the storage cellwith electric power till the cumulative power amount reaches a secondthreshold lower than the first threshold if the drive schedule datarepresents the vehicle is not to be used during the period.

(Supplementary Note 26)

A server device comprising:

a drive schedule reception means for receiving drive schedule data thatrepresents whether or not a vehicle is to be used during a predeterminedperiod in the future, the drive schedule data being received from acontrol device adapted to control a cumulative power amount that is anamount of electric power accumulated in a storage cell, the storage cellbeing charged with electric power supplied from an electric powergenerating system which generates electric power and supplying thevehicle with electric power for propulsion thereof,

a threshold cumulative power amount control means for determining alower limit of the cumulative power amount based on the received driveschedule data, the lower limit being a second threshold smaller than afirst threshold that is an upper limit of the cumulative power amount,and

a threshold cumulative power amount transmission means for transmittingthe determined second threshold to the control device.

APPLICABLE FIELD IN THE INDUSTRY

The present invention is applicable to power control systems that supplyelectric power to power accumulating systems including storage cells.

The invention claimed is:
 1. A power accumulating system comprising: apower accumulating system provided with a storage cell that is chargedwith electric power and supply a load with electric power, and a powercontrol device for controlling a cumulative power amount that is anamount of electric power accumulated in the storage cell, a driveschedule acceptance unit for accepting drive schedule data thatrepresents whether or not the load is to be used during a predeterminedperiod in the future, and a cumulative power amount control unit forcharging the storage cell with electric power till the cumulative poweramount reaches a first threshold if the accepted drive schedule datarepresents the load is to be used during the period, or otherwise,charging the storage cell with electric power till the cumulative poweramount reaches a second threshold lower than the first threshold if theaccepted drive schedule data represents the load is not to be usedduring the period.
 2. The power accumulating system according to claim1, wherein the control device is interconnected via communication linesso as to permit data communication among them.
 3. The power accumulatingsystem according to claim 2, wherein the control device receives thedrive schedule data from the server device, or sends the drive scheduledata to the server device.
 4. The power control system according toclaim 1 comprising: a plurality of the power accumulating systems and aserver device intercommunicating with each of the control devices of theplurality of the power accumulating systems, each control deviceincluding the drive schedule acceptance unit, and a drive scheduletransmission unit for transmitting the accepted drive schedule data tothe server device, the server device including a drive schedulereception unit for receiving the drive schedule data from the controldevice, a threshold cumulative power amount determination unit fordetermining the second threshold based on the received drive scheduledata, and a threshold cumulative power amount transmission unit fortransmitting a value of the determined second threshold to the controldevice, the control device including a threshold cumulative power amountreception unit for receiving the value of the second threshold from theserver device.
 5. The power control system according to claim 3, whereinthe threshold cumulative power amount determination unit is adapted toset the second threshold at a value that becomes smaller as the numberof the control devices transmitting the drive schedule data representingthe load is to be used during the period becomes greater.
 6. The powercontrol system including a power generating system for generatingelectric power according to claim 4, wherein the power accumulatingsystem is adapted to supply the electric power stored in the storagecell to the residuary load connected to the power generating system,wherein the server device includes an underpower estimation unit forestimating a deficit power amount that is an amount of electric powersupplied from the power generating system to predictably be short ofduring the period, and wherein the threshold cumulative power amountdetermination unit is adapted to determine the second threshold based onthe estimated deficit cumulative power amount and the received driveschedule data.
 7. The power control system according to claim 6, whereinthe threshold cumulative power amount determination unit is adapted todetermine the second threshold at a value that becomes greater as thenumber of the control devices transmitting the drive schedule datarepresenting the load is to be used during the period becomes greater.8. The power control system according to claim 6, wherein the poweraccumulating system includes a power supply unit adapted to generateelectric power and supply the generated electric power to the residuaryload connected to the power generating system, wherein the server deviceincludes a surplus power estimation unit for estimating a surplus poweramount that is an amount of electric power available to supply from thepower supply unit to the residuary load connected to the powergenerating system during the period, and wherein the thresholdcumulative power amount determination unit is adapted to determine thesecond threshold based on the estimated deficit cumulative power amount,the estimated surplus power amount, and the received drive scheduledata.
 9. The power control system according to claim 8, wherein thepower supply unit is adapted to generate electric power through at leastone of solar power generation and wind power generation, and wherein thesurplus power estimation unit is adapted to estimates the surplus poweramount based on weather data representing weather during the period. 10.The power control system according to claim 6, wherein the underpowerestimation unit is adapted to estimate the deficit power amount based onat least one of weather data representing weather during the period,calendar data representing calendar during the period, power consumptiondata representing an amount of electric power to predictably be consumedduring the period by the residuary load connected to the powergenerating system, and operation data representing running conditions ofthe power generating system.
 11. A power control method applicable to apower control system that includes: a power accumulating system providedwith a storage cell that is charged with electric power and supply aload with electric power, and a control device for controlling acumulative power amount that is an amount of electric power accumulatedin the storage cell, the power control method comprising: acceptingdrive schedule data that represents whether or not the load is to beused during a predetermined period in the future, and charging thestorage cell with electric power till the cumulative power amountreaches a first threshold if the accepted drive schedule data representsthe load is to be used during the period, or otherwise, charging thestorage cell with electric power till the cumulative power amountreaches a second threshold lower than the first threshold if the driveschedule data represents the load is not to be used during the period.12. A control device adapted to control a cumulative power amount thatis an amount of electric power accumulated in a storage cell that ischarged with electric power and supplies a load with electric power, thecontrol device comprising: a drive schedule acceptance unit foraccepting drive schedule data that represents whether or not the load isto be used during a predetermined period in the future, and a cumulativepower amount control unit for charging the storage cell with electricpower till the cumulative power amount reaches a first threshold if theaccepted drive schedule data represents the load is to be used duringthe period, or otherwise, charging the storage cell with electric powertill the cumulative power amount reaches a second threshold lower thanthe first threshold if the drive schedule data represents the load isnot to be used during the period.
 13. A server device comprising: adrive schedule reception unit for receiving drive schedule data thatrepresents whether or not a load is to be used during a predeterminedperiod in the future, the drive schedule data being received from acontrol device adapted to control a cumulative power amount that is anamount of electric power accumulated in a storage cell, the storage cellbeing charged with electric power and supplying the load with electricpower, a threshold cumulative power amount control unit for determininga lower limit of the cumulative power amount based on the received driveschedule data, the lower limit being a second threshold smaller than afirst threshold that is an upper limit of the cumulative power amount,and a threshold cumulative power amount transmission unit fortransmitting the determined second threshold to the control device.